Method of metal-plating.



E. L. WATROUS.

METHOD OF METAL PLATING.

APPLICATION FILED MAY 3. 1909. RENEWED FEB. 26. 1911.

Patented Apr. 3, 1917.

EDWARD I WATROUS, OF IDES MOIN-ES, IOWA, ASSIGNOE T0 15. L. WATBOUS eaavaiamme 00in any, 'a eoaronarron or sourn n nn'rnon or Ear-marine.

UTA.

"To all whom it may some" Be it known that I, EDARD L. WATROUS, a citizen of the United States, residin at Des Moines, in the county of Polk and tate of Iowa, have invented certain new and useful Improvements in Methods of Metal- Plating, of which the following is a specification.

The object of my invention is to provide an improved method of platin metal such as iron with non-corrosive meta such as zinc in a smooth and uniform manner so that articles such as bolts and nuts may be thus plated and the plating material thus applied will not interfere with the accurate fitting of the nuts on the bolts.

My invention consists in the arrangement and combination of the various steps of the process by which the objects contemplated are attained.

In the accompanying drawings, 1 have illustrated one form of apparatus by which the method may be carried out.

Figure 1 shows a top or plan view of a furnace for melting zinc and a receptacle therein to contain articles to be'plated.

Fig. 2 shows a side elevation of the furnace.

Fig. 3 shows a top or plan view of vice for applying centrifugal action to the recgptacle containing articles to be coated, an

Fig. 4 shows a central sectional view of same.

The reference numeral 10 indicates the walls of a furnace, and arranged within the walls is a tank 11 in which thezinc to be melted is placed. The receptacle for containing the articles to be coated is indicated by the numeral 12 and is provided with perforated sides. It also has at its top two handles 13. A rod 14 is provided to rest on top of the furnace walls and to extend through the handles 13 to support the vessel 12 in the melted zinc. The device for applying a centrifugal action to the vessel for containing articles to be plated comprises a base 15 having a stationary shield 16 thereon open at its top and bottom and widest at its bottom. Arranged within this shield is a rotatable support 17 having a frame 18 mounted thereon and desi ned to receive and su port the vessel 12. eneath the support 1 is a number of gas jets 19 for heat- 111g the suppo t.

Specification of Letters Patent.

a de- Patented Ar; 3, 191?.

. aenewearebmary 2c, 1917; Serial No. man.

In carrying out my improved method, I first place in the race tacle of thefurnace a quantity of zinc .or other platin material and by applying the heat of the urnace reduce same to a melted condition. I, then place the articles to be coated such, for instance, as bolts, nuts, and screws in the vessel 12. This vessel is then supported in the furnace with the articles to be coated immersed in the melted zinc. 'The articles are allowed to remain in the melted zinc' and the zinc is heated to such a temperature that the pores of the metal to be plated will open up and the plating metal will enter the pores to such an extent that the coating material will become homogeneous with the surface metal of the article to be coated. I then bodily remove the vessel containing the articles to be coated and instantly place same upon the rotatable support 17 which has been previously heated by means of the gas jets and which is maintained at a high temperature by the gas jets. I then cause the support 17,

- to be rapidly rotated with the result that the centrifugal actionwill cause all of the'superfluous plating material on the articles-to be coated to be discharged outwardly through.

' not chip or break off and which will be ,so

uniform in thickness that articles such as nuts and bolts may be thus treated and afterward screwed together without aflecting the accurate fitting of the threads.

In carrying out the process it is desirable that the vessel containing the articles to be coated be transferred quickly from the furnace in which they are treated to the zinc bath to the machine in which the centrifugal action is applied. For, if the articles to be treated become chilled during the transfer or during the time they are being placed in the centrifugal machine, the coating will become hardened either wholly or in part and thus prevent the superfluous coating material from being. discharged. It is also desirable that the rotatable plate on which the vessel containing the articles to be coated is placed be heated in such a manner as to prevent qhilling during the time the centrifugal action is being applied.

I claim 1. The method of treating metal articles, which consists in placing the articles loosely in a perforatedreceptacle, then immersing the receptacle contaming the articles 111 a bath of molten zinc by supporting said receptacle in a furnace containing said molten zinc and permitting the articles to remain in the molten zinc until the zinc alloys with the surface metal of the articles, then bodily removing the receptacle containing the articles and instantly subjecting it to centrifugal action, meanwhile maintaining the zinc in a molten state by applying heat thereto, whereceptacle and articles upon a rotatable support, while simultaneously heating the articles uniformly throughout and subjecting the receptacle and its contents to a centrifugal action whereby all excess zinc will be thrown off and a smooth uniform covering produced'on the articles.

3. The method of galvanizing small articles which consists in. placing the articles loosely in a perforat eceptacle, then immersing said receptacle in a .bath of molten zinc until the zinc alloys with the surface in a perforated receptacle, in immersing said receptacle together with the articles in molten zinc until a thorough surface alloy between the articles and the zinc takes place, in then removing and subjecting the articles and receptacle together to centrifugal action, whereby from the beginning to the end of the process of galvanizing, the articles are maintained in the'same receptacle and therefore can never come in contact with a surface cooler than themselves.

5. The method of treating metal articles which consists in placing the articles loosely in a perforated receptacle, then immersing said receptacle in a bath of molten metal until said metal alloys with the surface metal of the articles, then bodily removing the receptacle containing the articles and immedi ately subject-ing it to rapid centrifugal action without removing the articles therefrom until the excess coating metal is thrown of and a smooth uniform coating is effected.

Des Moines, Iowa, April 9, 1909.

EDWARD L. WATROUS.

Witnesses MILDRED B. LDIZEN, NELLIE M. AYLOR. 

